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<h1>Urea, CH<sub>4</sub>N<sub>2</sub>O</h1>

Urea (CH<sub>4</sub>N<sub>2</sub>O) is an organic compound that appears as white crystalline solid. It is highly soluble in water and is the primary nitrogenous end product of protein metabolism, produced by the liver and released into the bloodstream to be eliminated by the kidneys in the urine. Urea is also synthesized on an industrial scale worldwide and has a variety of applications. One of its most common uses is as a nitrogen-release fertilizer, providing an accessible nitrogen source for plant growth. Additionally, urea finds applications in the production of resins and plastics, and it is a component in many cosmetic and skincare products for its moisturizing properties. In the realm of optics, urea is notable for its ability to form birefringent crystals and has been used in some optical devices. However, when handling urea, especially in industrial settings, it's important to note that prolonged exposure can cause mild skin or eye irritation.

<h2>Chemical formula</h2>
CO(NH<sub>2</sub>)<sub>2</sub>

<h2>Other name</h2>
<ul>
<li>Carbamide</li>
<li>Carbonyl diamide</li>
<li>Carbonyldiamine</li>
<li>Diaminomethanal</li>
<li>Diaminomethanone</li>
</ul>

<h2>External links</h2>
<ul>
<li><a href="https://en.wikipedia.org/wiki/Urea">Urea - Wikipedia</a></li>
<li><a href="https://webbook.nist.gov/cgi/cbook.cgi?ID=C57136">Urea - NIST Chemistry WebBook</a></li>
</ul>
